A vehicle bumper device includes a bumper reinforcement, which extends in the direction of the width of a vehicle. Each end portion of the bumper reinforcement is coupled to one of a pair of coupling members (for example, side members), which extends in the front-rear direction of the vehicle.
The bumper reinforcement disclosed in Patent Document 1 is formed by a high-tensile steel plate, which is obtained through roll forming. The bumper reinforcement has a constant cross-sectional shape along the longitudinal dimension thereof. The bumper reinforcement is curved along an arc having a predetermined radius of curvature. The bumper reinforcement disclosed in Patent Document 2 is formed by a high-tensile steel plate, which is made through press forming. The bumper reinforcement has a substantially B-shaped cross-section. The cross-sectional shape of the bumper reinforcement gradually changes from the center of the bumper reinforcement toward either end portion.